Elderly Starches

Okay, technically I guess the term is “ancient grains”.

They are showing up everywhere these days. Even Cheerios has jumped on board.

What are Ancient Grains?

This term is used to describe grain species that have not been subjected to the modern breeding and selection practices that we have used for the last 200 years or so to modify present-day grains that are used in foods. In this way, ancient grains differ from commonly used ingredients of human and pet foods, such as wheat, corn, and rice. Several examples of ancient grains that you may see in human foods include Kamut (the predecessor of today’s wheat), millet, amaranth, quinoa, sorghum, spelt, bulgur, and oat groats.

From an environmental and sustainable standpoint, ancient grains are hardy plants that can thrive with reduced use of fertilizer, pesticides and irrigation practices. This reportedly makes these grains more sustainable and allows production practices that result in a lower carbon footprint. When consumed as whole grains, there also may be several health benefits to these senior starches. 

Evidence of Health Benefits?

Although limited, there is some evidence for health benefits when ancient grains are included in human diets. One study found that people consuming Kamut-containing foods showed reductions in LDL cholesterol levels and had positive changes in measures of systemic inflammatory responses. Consuming foods that contain millet may dampen glycemic response and improve feelings of satiety, a change that may reduce risk of diabetes and aid in diabetic control. Some of the phytochemicals that come along with these whole grains may also have antioxidant benefits.

Regardless, beware of hype. Nutritionists and scientists are still a long way from calling ancient grains the new wonder-food (although that does not stop marketing types from making such claims). Importantly, the Whole Grains Council notes that the benefits that are attributed to ancient grains probably have more to do with including the entire grain in foods and reduced processing than they do with any particular magical property of ancient grains. Common foods that are less highly refined, such as brown rice, whole grain pasta, oatmeal, and whole wheat bread appear to offer the same health benefits (without the exotic name and often at lower prices). In other words – whole grains are good, possibly regardless of whether or not they are ancient.

What about Dogs?

By now, we all know that any nutritional trend (or fad) that becomes popular in human diets will show up after a few years in dog foods. And, here they are, right on cue.

But, what do we actually know about including ancient grains in our dogs’ food? Can dogs efficiently digest and utilize these grains? Are there any demonstrable health benefits to feeding them?

Similar to their inclusion in human foods, there is not much science regarding ancient grains in dog foods. (Although, of course this has not stopped pet food marketing departments from promoting them far and wide…..). Two recent studies conducted by Dr. Maria de Godoy’s team at the University of IL do provide some information that can help you to decide whether or not you should look for these senior starches in your dog’s food.

The Studies

Study 1: The objectives of the first study were to examine starch and fiber compositions and digestibility values of five ancient grains (1). This study used an in vitro (laboratory) procedure. I have written about this approach and its advantages to both animal welfare and science before (see “Hearing Crickets?” and “Rawhide, Rawhide“). Basically, this is a validated, laboratory model of the digestive and fermentative processes that take place in a dog’s gastrointestinal tract. Although not perfect, this set of procedures allows pre-screening of a multitude of ingredients, providing evidence for how well they will be digested and utilized in an actual canine stomach and intestines. In this experiment, the tested grains were amaranth, white proso millet, red millet, quinoa and oat groats. The grains were compared to each other and also to a negative control (cellulose) and a positive control (beet pulp).

Results: There were several differences among the five ancient grains with respect to the level of resistant starch (amaranth was highest), the concentration of free glucose (amaranth and quinoa were highest) and the concentration of glucose originating from the digestion of starch (millet and oat groats were highest). Regardless of these differences, all of the ancient grains provided a source of dietary starch that was highly digestible along with fiber that was moderately fermented (an attribute that is considered to be beneficial).

Study 2: The second study was a feeding study with dogs (2). (Editorial note: I LOVE this. This is how science should work, folks. Begin with an in vitro study and only move on to tests with dogs when you have evidence of positive and safe results. Kudos to these researchers!).

Okay, onward.

The study included a group of 10 adult, female beagles who were fed foods that contained either amaranth, white proso millet, quinoa, oat groats, or rice (the control) as the primary starch source. Dogs were fed for a period of 14 days using a replicated 5 X 5 Latin Square study design. In this type of design, each dog is randomly fed each food for 10 days, followed by a 4-day period during which feces and urine were collected for analysis. Post-prandial glycemic responses (blood glucose response to a meal) was conducted on the final day of each 14-day period. Measurements included food and nutrient digestibility, glycemic response, and gut microbiota changes (see “Your Dog’s Microbiota” for more information).

Results: The ancient grains performed quite well in this study (go oldies!), with several significant findings:

  • Digestibility values: All five of the foods had moderate digestibility values, ranging between 82 and 86 %. Of the four ancient grains, white proso millet-containing food had the highest dry matter digestibility value of 86 %. Of the four ancient grains, the digestibility of quinoa was lowest.
  • Fiber: The millet-containing food also had the highest fiber digestibility (fermentability) value, when compared with other grains. This finding suggests that millet contains a higher proportion of soluble or fermentable fibers, a difference that may be important in terms of its ability to provide prebiotic benefits when included in a food.
  • Fecal microbes: Moderate changes were observed in several gut microbe families, but overall bacterial species richness and diversity were not significantly impacted by feeding different grains. Basically, though there were some small changes in certain species, the gut microbiome of the dogs remained healthy when fed ancient grains.
  • Poops: Fecal scores (i.e. poop quality) were normal for all of the foods. Total fecal output (something that is often important to dog owners), differed though. The quinoa and amaranth-containing foods produced more feces (~ 68 grams/day) compared with the white proso millet-containing food (~ 46 grams/day). These differences were attributed to differences in water-holding capacity (ability of the starches and fibers to hang on to water) of the different grains.

Take Away for Dog Folks

So, what does all of this mean for our dogs? Is there enough positive evidence to warrant selecting foods that contain ancient grains for your dog?

Well, as many things in life, based upon the science that we currently have, it depends.

Primarily, it depends on expectations.

If you are interested in selecting foods that include less highly processed (refined) grains that may be associated with a reduced environmental impact, then ancient grains could be your grain.

If your goal is to provide a digestible starch source that comes along with moderately fermentable and beneficial fibers, again, ancient grains may be your starch. (But remember that more common whole grains may perform similarly in foods).

However.…if, as some marketing hype suggests, you expect ancient grains to be the new holy grail of food ingredients, then it would be smart to rein that in. There is nothing nutritionally magical about amaranth, Kamut, oat groats, millet, or quinoa (other than perhaps being somewhat difficult to pronounce). While these grains are well-digested and accepted by dogs and provide good sources of fiber, other benefits that directly impact health and wellness have not been demonstrated.

And not to put too fine a point on this, but most likely they never will be. Remember that ancient grains are simply early domesticated grains that have not been intensively selected for hardiness, high starch content and harvesting ease. It must also be noted that no one has yet compared the nutritional performance of ancient grains with that of modern whole (unrefined) grains, such as whole grain wheat, brown rice or barley. It is quite possible that the whole grain versions of modern-day grains would perform similarly when in the gastrointestinal tracts of dogs when compared with the ancient grains.

Ancient grains just sounds so much cooler than whole wheat…….

Cited Studies

  1. Traughber ZT, He F, Hoke JM, Davenport GM, de Godoy MRC. Chemical composition and in vitro fermentation characteristics of ancient grains using canine fecal inoculum. Journal of Animal Science 2020; 98:1-8. doi:10.1093/jas/skaa326
  2. Traughber ZT, He F, Hoke JM, Davenport GM, de Godoy MRC. Ancient grains as novel dietary carbohydrate sources in canine diets. Journal of Animal Science 2021; in press.

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3 thoughts on “Elderly Starches

  1. Pingback: More Human-Grade Research… and a Rant – The Science Dog

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